Rato R999 Combustion Engine (35 HP | 28.6 mm shaft)

How much power does the Rato R999 engine have and what is its displacement?

The Rato R999 engine (35 HP) has a displacement of 999 cm³ and, according to the manufacturer's catalogue (model R999D), a net power of 25 kW at 3600 rpm and a torque of 68 N·m at 2500 rpm. It is a twin-cylinder, four-stroke unit with an electric starter. For comparison, the Rato R420 produces 8.8 kW (12 HP) from 420 cm³, so the R999 is almost three times more powerful. That output is enough to drive construction machines with high power demand, for example a ride-on power trowel with a 2 × 1200 mm troweling diameter.

What shaft does the Rato R999 engine have and how does it differ from the standard R999D?

This version of the Rato R999 engine has a shaft diameter of 28.6 mm (1 1/8 in). According to the manufacturer, the standard R999D has a 36.5 mm PTO shaft, which is 7.9 mm thicker, so the engines cannot be swapped without adapting the parts mounted on the shaft. Before buying a replacement engine, measure the shaft of your current engine with a caliper and compare it with 28.6 mm.

Which machines is the Rato R999 engine suitable for?

The Rato R999 engine (35 HP) drives the Toolsa TPT-1046 EHG ride-on power trowel with a 2 × 1200 mm troweling diameter and 8 blades. It suits machines that require about 25 kW net (35 HP) and have a 28.6 mm input shaft. Before buying, check the machine documentation for power, shaft diameter and the way the engine is mounted to the frame. If you are not sure, write to us through the contact form.

How do I choose a Rato combustion engine for my machine?

Engine selection starts with three parameters: power, shaft diameter and the mounting to the frame. Rato engines come with 25 mm, 25.4 mm, 28.6 mm and 36.5 mm shafts, and their power rises from 4.3 HP (RV170) to 35 HP (R999). The shaft diameter must match the clutch, pulley or gearbox mounted on it. The new engine should have the same power as the original or higher, provided the machine manufacturer allows such a replacement.

How much oil does the Rato R999 engine hold?

The Rato R999 engine holds 2.4 l of engine oil. The manufacturer gives that capacity in the catalogue, and the data sheet of the Toolsa TPT-1046 EHG trowel, which uses this engine, confirms it. For comparison, the oil sump of the Rato R300, R390 and R420 engines holds 1.1 l, which is more than twice less. Check the oil level before every start on a level surface, and change the oil and filters according to the engine manufacturer's manual.

What is the difference between the Rato R999 35 HP and the Rato R420 12 HP?

The Rato R999 offers 25 kW net (35 HP) from 999 cm³, while the Rato R420 offers 8.8 kW (12 HP) from 420 cm³, so the R999 is 16.2 kW more powerful. The R999 has a 28.6 mm shaft and the R420 a 25 mm or 25.4 mm shaft. The oil sump holds 2.4 l in the R999 and 1.1 l in the R420. The R420 drives lighter machines such as compactors, generators and motor pumps, while the R999 drives high-power machines, for example ride-on power trowels.

Does the Rato R999 engine have a fuel tank?

The Rato R999 engine has no fuel tank. In the catalogue the manufacturer enters “No tank” for the tank capacity, so the tank and the fuel system are provided by the machine the engine works in, for example a power trowel. The engine, with a displacement of 999 cm³ and a net power of 25 kW, has a carburetor and an electric starter. Before buying, check that the machine you are fitting the engine to has its own tank and fuel lines.

What are the dimensions and weight of the Rato R999 engine?

According to the manufacturer's catalogue, the Rato R999 engine (model R999D) measures 515 × 481 × 558 mm and has a net weight of 50 kg. For comparison, the smaller Rato R420 weighs 32 kg and measures 465 × 413 × 440 mm. Before fitting, check that the machine frame has room for an engine 515 mm long and 481 mm wide, and remember that the net weight does not include packaging.